Health Effects of Chronic Pesticide Exposure: A Narrative Review of Neurological, Carcinogenic, Reproductive, Metabolic, and Systemic Implications

Abstract

Chronic pesticide exposure represents a critical global public health challenge, particularly in low- and middle-income countries characterized by inadequate regulatory oversight and poor occupational protection. While acute poisonings are well-documented, sub-acute chronic exposures are increasingly linked to long-term systemic pathologies. This study synthesizes multi-disciplinary evidence linking chronic pesticide exposure to systemic human diseases while critically appraising the methodological strengths and limitations of the current literature. A comprehensive search of major biomedical databases (PubMed, Scopus, Web of Science, ScienceDirect, and Google Scholar) identified key prospective cohorts, meta-analyses, systematic reviews, and mechanistic studies published between 2000 and 2026, alongside foundational pre-year 2000 literature. Convergent epidemiological and experimental data robustly associate chronic exposure with neurodegenerative conditions (Parkinson’s and Alzheimer’s diseases), specific malignancies (non-Hodgkin lymphoma, leukaemia, breast cancer), reproductive disorders, and metabolic dysregulation, including type 2 diabetes. These pathologies are driven by shared molecular pathways: oxidative stress, mitochondrial impairment, endocrine disruption, neuroinflammation, genotoxicity, and epigenetic alterations. Notably, prenatal and pediatric cohorts exhibit heightened susceptibility due to developmental vulnerability and immature metabolic detoxification. Although exposure misclassification, chemical mixture complexities, and residual confounding problems tend to limit definitive causal attribution for individual compounds. This aggregate evidence warrants decisive public health intervention. Mitigating this burden requires expanded prospective biomonitoring, global regulatory harmonization, and the accelerated adoption of integrated pest management frameworks.